There are 750 so-called “package treatment plants” in Kentucky, each treating between 5,000 and 50,000 gallons of wastewater every day. Larger areas—like Louisville—have been phasing out the smaller plants, which are prone to failure. But that solution is out of reach for some smaller communities, and for the past few years one area in Bullitt County has been plagued by sewage releases from a nearby plant. The most recent one was last weekend.

You can smell the creek that runs through Lynn Hestla’s backyard in Hillview before you can see it. The stench of sewage permeates the air. It smells awful. And Hestla says sometimes it’s much worse.

“It’s like walking into an old-time outhouse that’s never been cleaned,” she said. And that’s on a bad day. She tells me the smell right now isn’t bad—it’s normal for the neighborhood.

Seeing partially-treated sewage float down the creek has also become normal for Hestla and her neighbors. When a mechanical failure happened at the Bullitt Hills wastewater treatment plant last weekend, it was the latest in several similar incidents over the past few years.

“Basically a piece broke in one of the treatment processes,” Charlie Roth said. He’s with the Kentucky Division of Water’s Louisville Office. Roth says the Bullitt Hills plant has had recurring problems. Many of those issues stem from the fact that it’s what’s known as a package treatment plant—a way of treating sewage that’s still in use throughout Kentucky but becoming obsolete.

“There’s not really any redundancy built into them,” he said. “So if one process breaks down, there’s not a backup that they can use while they fix it.”

So when a component went bad this weekend in Bullitt County, the plant kept pumping as usual. It pumped sewage into an unnamed tributary of Tanyard Branch, which flows into the Salt River, and eventually the Ohio.

Package plants are basically small-scale versions of larger sewage treatment plants. Bullitt County Sanitation has eight of them. In Jefferson County, the Metropolitan Sewer District has whittled down the package plants in its service area from about 350 to 16.

MSD Interim Chief Engineer Steve Emly says one of the limitations of package plants is that they’re temporary solutions that many communities end up using permanently.

“Most of these structures are steel structures and over a service life of 25-30 years, they begin to deteriorate just from exposure to the elements as far as rust,” Emly said.

So, many of the older package plants—like Bullitt Hills—are deteriorating. They don’t have any backups in case of equipment failure. And then, many don’t have alarms to let operators know when something goes wrong. Bullitt County Sanitation District Manager Jerry Kennedy says he didn’t know there was a problem until a neighbor called.

“We found out by one of the neighbors giving me a call,” he said. “And ‘Jerry,’ she said, ‘you always asked me if something went wrong or something wasn’t right to call you.’”

When people see sewage flowing behind their houses, they can’t necessarily count on the state to act fast, either.

The state Department for Environmental Protection has a hotline to report environmental emergencies. A tip was called in on Monday—three days after sewage started flowing into the creek. The Division of Water…responded Tuesday.

“Calls come in all the time,” said spokeswoman Allison Fleck. “A determination has to be made at that time—does this fall into routine notification, or an emergency?”

Fleck says the department considers certain events emergencies: fish kills, large chemical leaks, or anything that creates a sheen on the water. A release of raw sewage from a small package plant doesn’t fall into any of those categories.

“It’s unpleasant, it’s more of an aesthetic,” Fleck said. “Yes, it needs to be dealt with, but it didn’t constitute an emergency.”

Kentucky can fine the Bullitt County Sanitation District for the release, and for failing to report the event to the state.

But it’s more economical for the deliquent district to keep paying fines than to eliminate their package plants—manager Jerry Kennedy estimates it would cost the county more than $50 million to eliminate the plants in favor of more sophisticated treatment options.

“And when you only have about 3,800 customers, it’s just hard to spread that over the customers for a 20-30 year bond issue to do this,” Kennedy said. “So you know, economics does step in to a certain extent. So we upgrade and try to do the best we can with what we got.”

Standing by the polluted creek, Lynn Hestla shakes her head when I ask if the fines are effective.

“They just keep on fining them and they keep on paying it,” she said. “And it starts back over again, the whole routine.”

As of Wednesday afternoon, the plant was repaired, and officials say the creek should be cleaned by the end of the week.